After I finish my airsoft shotgun which shall be done next weekend... I hope , I want to build a marble rifle. I want it to be portable so I dont have to be carrying around a compressor, or bike pump. SO I guess if I went pneumatic I would have to go with co2 or a HPA tank. Or I can go with a simpler combustion powered by butane(smaller than propane tank). I think I want to lean toward combustion becuase Butane is so much smaller than a hpa or co2 tank, and It may deliever around the same FPS?

So I just wanted to know what you guys have to think about it. I also plan to add a scope, laser sight, and some kind of crosshair setup. Im going to be using it for LONG LONG range stuff. So what you guys think?

P.S.

normal sized marbles, like the catseyes marbles you can find at drug stores.

Spec list:

Fully Steel or copper

Going to be co2, Hpa, or a combustion Butane propellent

Shoots noraml sized marbles

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Last edited by CannonCreator on Sun Sep 09, 2007 2:34 am, edited 1 time in total.

Pneumatic cannons can give consistent performance and will be more powerful than combustions. With that said, a marble rifle will probably have a small chamber so a mounted pump will not take long to fill it up. Portability and power in one package.

Marbles will curve in the air, no point with a scope.You think it will deliver around similar FPS? Well you give us no specs of the valve you would use or the pressure you would run it at as a pneumatic so I can't answer that but if you did have CO2/HPA and a decent valve it would kick ass compared to butane combustion.

How far is long range? Please be a bit more specific when asking questions.

I was just wondering because my paintball marker puts backspin on a paintball (courtesy of the Tippmann Flatline). The paintballs, although not perfectly round, tend to fly a lot straighter and further.

Maybe one could put some type of fine sandpaper on the top of the barrel's interior to get it spinning.

Edit: I searched on the topic of backspin. There was nothing definite but noname made a comment about cutting a small gap in the top of the barrel and putting an o-ring around the barrel to rest in the gap. This would probably work great to generate backspin on a marble, and also act as a detent (stopper) to keep the marble from rolling out of the barrel. Also, if the desired backspin wasn't accomplished with the o-ring, simply add another until the results are reached.

MrCrowley wrote:Marbles curve because they are spherical and perfectly round. The only way to stop them is to rifle your barrel.

...or have a vented barrel ...or as has been suggested, induce back spin, which also flattens the trajectory - not quite as accurate, but less arcing to worry about.

And I second the RANDOM capitalisation comment, especially about COPS.

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Novacastrian:How about use whatever the heck you can get your hands on?frankrede:Well then I guess it won't matter when you decide to drink bleach because your out of kool-aid....I'm sorry, but that made my year.

I presume that spherical objects curve because they are given a spin in the barrel. To avoid this impacting accuracy in a negative way, we can simply make sure this spin is consistent.I can think of two ways to do that:1) Prevent the marble from spinning at all, by, say, epoxying a golf-tee to it.2) Make the spin consistent, by adding a hop-up mechanism.

If you just want to plink the crap out of stuff in your backyard, Marbles work excessively good at a range from 20m (this is the maximum i shot).So unless your wanting to pick a small target off from 30m+ just build it and plink stuff.

use lead fishing sinkers, they go alot straighter than marbles do at a longer range but, that being said you will loose some velocity.

personally i use marbles for 10-15m and sinkers for 15+ and have shot sinkers accurately at 30 or so meters.

also i would like to add that i have found that shooting marbles at 100-150psi is quite accurate like a 300x200mm target at 20m consistently with a red dot-optic scope, anything above this though the marbles will curve like a b1tch like 5m to the left or right after traveling 10m forward.